Charles james fatjvel



2 SheatsS11e et 1. 0. J. PAUVEL.

PURNAGB POR THB TREATMENT 0F RBTRAGTORY GRES.

Patented Mar. 7, 1893.

W//l//l/l/ (No Model.)

wv'nesses (No Model.) 2 Sheets-Sheet 2.

C. J. FAUVEL.

EURNAGB POR THB TREATMENT 0F RBPRAGTORY ORES.

No. 493.076. Patented Mar. 7, 1893.

FIGZ.

NTTnD STATES PATENT OFFICE.

CHARLES JAMES FAUVEL, OF LONDON, ENGLAND.

FURNACEFOR THE TREATMENT OF REFRACTORY ORES.

SPECIFICATION formingrpart of Letters Patent No. 493,076, dated March 7, 1893.

Application filed April Z5, 1892.

To a/ZZ whom it may concern:

Be it known that I, CHARLES JAMES FAU- VEL, assayer and mining engineer, of 15 George Street, Mansion House, in the city of London, England, have invented an Improved Furnace for the Treatment of Refractory Ores; and I do hereby declare the following to be a full, clear, and exact description of the same.

This invention relates to the treatment of refractory ores containing precious and other metals, and it consists essentially of an improved furnace whereby the operation of oxi dizing the impurities associated with or forming part of the ore may be elfected by a current of hot air entirely out of contact with the furnace gases so that the ore will not be exposed to'the chemical action of the said gases or be contaminated by the formation of any carbonaceous deposit therefrom, but, after undergoing the process of oxidizing, will be delivered in what is technically known as a sweet condition. To accomplish this oxidizement and sweeteni'n git is essential thatthe current of air which is to eifeot the oxidation should not be robbed of its oxygen to support the combust-ion of the fire and accordingly the oxidizing current is separately heated and the passages are so arranged thatneither the ore nor the oxidizing current can at any time come in contact with the products of combustion of the fuel, while the flues for the latter are so arranged as to insure the utilization in a rational manner and to the utmost possible extent of the available heat.

The furnace is also applicable for chloridizing the silver contained in the ore for which purpose it is only necessary to add the requisite amount of chlorinating medium to the ore.

This improved oxidizing and ore sweetening furnace is illustrated in the accompanying drawings, forming part of this specification, and y will be described with reference thereto.

Figure l is a longitudinal sectional elevation of the entire furnace. Fig. 2 is a vertical section on line -m Fig. l. Fig. 3 is a central detail section looking in the reverse` direction to Fig. l.

Seiial No. 430,497. (No model.)

It comprises a fireplace A of -suitable construction, an air-heating chamber B, an oxidizing tower C, settling chambers D, E, El', E2, and a chimney F, with heir various iues, chutes and other adjuncts constructed and arranged for effecting the oxidizing operation as hereinafter described with reference to the drawings in which the feathered arrows indicate the course followed by the products of combustion while the featherless arrows indicate the course of the oxidizing current.

The fireplace A is so constructed as to burn any fuel, air holes being provided in the side walls to admit air and insure perfect combustion. It is preferably built in duplicate to give a greater command of heat at starting or whenever required.

The oxidizing tower C in whichthe oxidation of the sulphides &c., is accomplished is a rectangular brick structure about forty feet high, fitted internally with a series of inclined ireclay slabs G each slab extending the full width of the oxidizing chamber and projecting alternately from the opposite walls by which they are supported as shown in Fig. l so that the pulverized ore supplied at the top of the tower must slide down these slabs in succession, the slabs being so arranged with regard to each other that the lore will be delivered by each slab on to the highest partof the next below and so on from one to another throughout the whole series so that the whole superficial area ot' the slabs is utilized as heating surface for the ore which is finally received in the first settling lchamber D at the bottom of the tower. clined slab d forming one side of this settling chamber that the greatest heat is developed,

lthis being the point at which the gasesfrom the furnace enter the iiues H, H of the oxidizing tower. These fines H extend beneath each of the inclined slabs G and communicate with vertical fines H in the end walls of the tower which are so interrupted by crosspartitions h that the furnace gases will becaused to follow a zig-zag course such as indicated by the feathered arrows so as to pass through all the dues H in succession from the lowest upward, the highest flue l-I finally leading into the upper end of a central downcast Itis beneath the influe K leading into a cross-Hue L situated beneath the other inclined slab CZ of the settling chamber D and communicating by a side passage at the opposite end with a flue M leading direct to the chimney F. None of these flues has any connection with the interior of the oxidizing tower so that the furnace gases cannot come in contact with the ore or the oxidizing current, while the course of the furnace gases as well as that of the oxidizing current being upward, and inverse to that of the falling ore, the latter is subjected to a gradually increasing temperature, the maximum degree of heat being attained at the completion of the operation. In this way the heat is developed and utilized in the most rational manner for progressively effecting and finally completing `the oxidation of the ore. Each flue His inclosed at the underside by a tireclay slab h which is also available as heating surface for the oxidizing current which, in ascending through the oxidizing tower, strikes against these underside slabs and takes up heat therefrom.

The pulverized ore is supplied at the top of the oxidizing tower, by an automatic feeder (preferably consisting of a Iluted cylinder working in a hopper N) which distributes the ore in the form of a thin stream extending across the whole width of the tower and falls upon the hot sloping surfaces G rolling down them in a constant stream, the particles being raised to a state of incandescence by contact l with the slabs.

During their passage down l the inclined slabs, and in falling from ,one to the next, the ore particles encounter an abnnl dantl upward stream of hot air supplied from the air heater B. above the fire place A and is divided by baf- The air heater is situated ties I) and provided with air inlets furnished with dampers to regulate the air supply to i suit the ore under treatment.

Theair having g been heated to the proper temperature passes out of the heater through lateral and. cross fines B B2 B3, asindicated by the featherless arrows, in to the upper part of the first settling chamber D and flows up through the oxidizing tower meeting the incandescent particles of falling ore, checking their descent and scattering them in such a way that no particle can escape the complete oxidation and removal of its associated sulphur, arsenic, antimony ortellurium compounds. Moreover, the l stream of heated air on entering the first settling chamber D not only helps by its own temperature, and by perfecting the oxidation the fumes and passes off at the top of the tower into a downcast flue O leading to the series of settling and condensing chambers E E E2 wherein any solid particles that may be carried olf along with the oxidizing current are caught and wherein the sulphurous and other fumes are condensed by Contact with the cooled surfacesof metal tanks P, through which a constant circulation of cold Water is maintained, the air and vapors passing on into the chimney F and being thus freed of noxious properties, before being allowed to escape.

Reverting now to the product of the oxidizing process, the oxidized and sweetened ore is discharged from the settling chamber D through a discharge pipe Q (provided with a regulating valve q) into a quick running stream R of cold water contained in atrough into which the pipe Q dips whereby the pipe is sealed against the admission of cold air. It is necessary to keep the water in a turbulent state otherwise the bubbles of steam may cause `the particles to lioat on the surface of the water, instead of being immediately immersed. The constant agitation .of the water and the complete immersion of the glowing particles may be conveniently effected by the introduction in the pipe Q of jets of cold water at S which meet the falling stream of particles and increase the force with which they descend into the trough. The sudden cooling of the glowing particles of ore thereby elfected, and the disruptive effect produced by the flashing of the water into steam cause the breaking up of the particles and of any glaze-like coating or adherent oxides of the base metals, which are carried oif by the running water, thus freeing the noble metals of impurities which would be `detrimental to the subsequent amalgamating or other metal saving operation. The particles are transported by the running stream to a series of settlers, amalgamators or other means of arresting and collecting the heavier and valuable metals contained in the ore. As by this quenching operation the ore is reduced to an almost impalpable powder very tine crushing is not necessary and therefore the output of the crushing mill can be increased. Moreover, the particles are so minnte that there is' no longer any room for atoms of gold or other metal to be locked up in them and the skin of oxide having been removed, as above mentioned, the gold is clean and in a condition specially adapted for amalgamation.

The settling chambers E E E2 are provided with discharge spouts e closed by valves, at which the particles intercepted and the sulphurous and other vapors which have been condensed may be periodically discharged into trucks below.

In order to insure a sufficient draft in the chimney to draw the air through the air heater and through the oxidizing tower and condensing chambers, and likewise to draw the furnace gases through the fines above described,

IOO

IIO

493,076- Y i v a special draft furnaces T wouldbe provided, communicating directly with the chimney, and over them, air-heating chambers V, connected by a ue with chamber D, for the supply of hot air thereto, should the supply from the air heater B before described be insufflcient. Retorts for the generation of oxygen or chlorine gas, may be arranged in ork above the furnaces T for supplementing'or replacing as the case may be the oxygen of the hotair supply when required.

Having now particularly described and ascertained the nature of the said invention and in what manner the same is to be performed, I declare that what I claim is l. In a furnace for the treatmentof refractory ores, an oxidizing tower or shaft having a series of inclined shelves projecting within the shaft alternately from opposite sides thereof, in combination with horizontal transverse iiues formed beneath such shelves and'convnected with each other in zig zag order bv vertical end iiues, the lower end of the series being connected with af urnace adjacent to the tower so as to receive the furnace gases therefrom, whereby the shelves will be heated by the furnace gases passing through the said horizontal flues, substantially as specified.

2. In a furnace for the treatment of refractory ores, an oxidizing tower or shaft having a series of inclined shelves projecting within the shaft alternately from opposite sides thereof, in combination with horizontal transverse hues formed beneath such shelves and connectedwith each other in zig zag order by vertical end flues, the .lower end of the series bein g connected with a furnace adjacent to the tower, so as to receive the furnace gases therefrom and at top to a down flue leading beneath the settling chamber at the foot of the tower and thence to the chimney, substantially as specified.

3. In a furnace for the treatment of refractory ores, an oxidizing tower or shaft provided with a series of inclined shelves projecting within the shaft alternately from opposite sides thereof and with transverse iiues formed beneath saidshelves connected together in zig zag order by end fiues and connected with a furnace so as to receive thefurnace gases therefrom, in combination wit-h an air heater situated above but having no communication with the furnace and connected with the lower end of the shaft or tower so as to supply acurrent of heated air thereto which flowing upward through the shaft or tower meets the stream of falling ore passing over the shelves, as described. Y

4. In a furnace for the treatment of refractory ores, an oxidizing tower or shaft provided with alternating inclined shelves having iiuesV beneath them connected together in zig zag order and connected with a furnace so as to receive the furnace gases therefrom, an air heater above the furnace connected with and 'forsupplyinghot air to the `interiorof the kfrom the shelf'flues ofthe tower, substantially as specified.

5. In a furnace for thetreatment of refractory ores, comprising an oxidizing tower or shaft having a series of internally-projecting alternating inclined shelves heated by flues beneath coupled in zig zag order and connected with a furnace as described, ,and an air heater for supplying an upwardly flowing current of hot air to the interior-of the tower or shaft, the combination with the receiving and settling hopper at the foot of the tower, of a' vertical spout larranged to be sealed by dipping into running water and containing perforated jet pipes at which jets 'of cold water are projected across said spout so as to meet and quench the freely-falling stream of ore particles, substantially as specified.

6. In a furnace for the treatment of refractory ores', comprisingan oxidizing tower or shaft having a series of internally-projecting 9 5 alternating inclined shelves heated by flues beneath coupled in zig zag order and connected with a furnace as described, the interior of the tower or shaft being connected at bottom with an air heater as described, forV roo supplying an upwardly flowingcurrent ofr4 hotl air through said tower, the combination with said tower, of a series of settling chaln- K bers for intercepting particles carried over by the air current, the chambersbeing connected ro 5 I on the one hand with the upper end of the tower or shaft by a down ue and on the other hand with the chimney, as described.

7. In a furnace for the treatmentof refractory ores comprising an oxidizing tower or 11o shaft having a series of internally-projecting alternating inclined shelves heated by iiues beneath connected in zig zag order and connected with a furnace as described, the in terior of the tower or shaft beingl connected at bottom with an air heater, as described for su pplying' an upwardly flowing current of hot air through said tower, the combination with said tower, of a series of settling and condensing chambers for intercepting the parti- 12C cles carried over by the air current, said chambers being connected on the one hand with a down fine leading from the top of the tower f or shaft and on theother hand with the chimney, and containing hanging water bridgesor t2 5 tanks through which cold water may circulate for providing cold surfaces within the chambers for condensing the fumes, substantially 'as specified.

8. A furnace for the treating of vrefractory 13o ores, comprising a tower having internallycurrent and fumes so as to avoid loss of heat, projecting alternating inclined shelves with substantially as specified. flues beneath them connected together in zig Dated this Sth day of April, 1892. zag order and connected with a furnace as l 5 described, and having a down lue for the CHARLES JAMES FAUVEI' furnace gases connected with the uppermost Vitnessesr:

shelf flue and a down Hue for the oxidizing WM. CLARK, current and fumes, the down flue :for the fur- Patent Agent, 53 Chancery Lane, London. nace gases being situated between the oxidiz- T. XV. KENNARD,

1o ing shaft and the down flue for the oxidizing 53 Chancery Lane, London, Clerk. 

